Many back-to-school essentials are already cheaper online than they are in stores. Get a head start on shopping with the best deals from Amazon, Staples and Best Buy on everything from JanSport backpacks and graphing calculators to notebooks, pencils and more.Original price: $110.85Graphing calculators can be one of the biggest back-to-school expenses. Right now, Amazon has the Texas Instruments TI-84 — a model commonly required for math classes — for less than $100. If you're looking to spend less, Staples also has the Casio FX graphing calculator, which offers many similar features and comes in pink.Original price: $40JanSport backpacks are a staple, but Amazon currently offers some of the best prices. Pick up a classic JanSport backpack in a variety of colors for just $36, beating in-store prices by $20. If you need extra space, Staples also has a floral JanSport laptop backpack. READ MORE: Buy it for life: Durable products worth every dollar (now on sale)Original price: $129.99Save $31 on Apple's AirPods 4 at Amazon, where they're on sale for just $99. Staples also has the earbuds on sale, but for $117. The latest generation features improved sound quality and a more comfortable fit.Get an 18-pack of classic yellow pencils from Amazon for just $4. If mechanical pencils are on your shopping list, Staples offers a better value with a 40-pack for only $10.Original price: $11.49Amazon has one of the best deals on Pilot pens, with a four-pack marked down by more than 50%. For comparison, Staples charges about $10 for a three-pack of fine-point Pilot pens, while Amazon's four-pack costs just over $5.Original price: $9.31After comparing prices at Amazon, Staples and Best Buy, Amazon offers the best deal on this six-pack of Mead notebooks thanks to a 25% discount. The set includes six colors, making it easy to organize notebooks by class.READ MORE: 21 small Amazon buys that make everyday tasks easier, from just $4Original price: $89.99Amazon and Best Buy are tied on price for the HP DeskJet 2955 printer at $69.99, a savings of $20. Both retailers also include three months of Instant Ink with your purchase.Original price: $19.53Five Star binders cost more than $30 at Staples and Best Buy, but Amazon has them for about $20, saving you more than $14. If color isn't a priority, the red version is an even better value at just $17.Original price: $5.56Amazon comes out ahead again with some of the best prices on Crayola supplies. A two-pack of Crayola crayons costs just $13, while a single-pack at Best Buy is priced at $31. You can also pick up a 12-count of Crayola markers for just $6.READ MORE: Save up to 80% on summer essentials, from cooling pajamas to sandalsAmazon has kids' Owala FreeSip water bottles for $25 in a variety of fun colors, making it an easy stop for a back-to-school essential. Choose from bright combinations like mint green and brown or orange and navy.Original price: $9.97No matter where you shop, it's easy to save on Elmer's glue sticks right now. Amazon has a 30-count pack for just over $7, while Staples offers a six-pack for $4.READ MORE: Save 40% off or more on back-to-school essentials from HP, Anker, JanSport and moreOriginal price: $22.99Best Buy has the best price on this Logitech wireless mouse at just $15, a 35% discount. The battery lasts up to 18 months, making it a practical pick for school or work. A similar model on Amazon costs about $30, even on sale.For more Deals, visit www.foxnews.com/dealsWith a new Minions movie in theaters, this Simple Modern Minions backpack from Amazon is a fun back-to-school pick. It features multiple storage pockets, including a padded laptop sleeve. For a more collectible option, Kipling also offers Minions-themed backpacks, pencil cases and tablet bags.If you’re an Amazon Prime member, you can get these items sent to your door ASAP. You can join or start a 30-day free trial to start your shopping today.